Erosion resistance of needled carbon/carbon composites exposed to solid rocket motor plumes

The erosion resistance of the needled carbon/carbon composite leading edge was investigated by exposure to the solid rocket motor (SRM) plume. The erosion morphology and microstructure were examined and associated erosion mechanisms discussed. The composite leading edge was severely damaged with large recession and erosion rate after exposure. The results suggest that the erosion behavior was determined by the weak needling structure of the leading edge windward with small thickness in the severe environment of the plume impingement. Erosion mechanisms were combined effects of thermochemical ablation by oxidizing species and thermomechanical erosion by both aerodynamic force and alumina particles. The former weakens the strength of the composite while the latter contributes primarily to high erosion rate in the oxy-lean SRM plume environments.